The main objective of this research is an extended cooperation between the Research Institute on Leukemias and other Blood Diseases and C.A.L.G.B. Up to 1975, our contribution to A.L.G.B. totaled 538 patients records with A.L.L. or A.M. From June 1975, we entered into C.A.L.G.B. protocols 64 patients of whom 32 had A.M.L. and 32 other malignancies. Our aim is to increase our direct participation for acute leukemias through participation to the next A.L.L. protocol, and to extend our contribution to other malignant diseases. These goals require an increasingly active liaison of the Paris Group with other French or European hematological Centers and the development of activity of the Chemotherapy Unit beyond blood malignant diseases, through more close collaboration with surgeons and radiologists. Since 1974, 68 French hematological departments follow our protocols and send us their records. Since the same time, the melanoma group of Hospital Saint-Louis studies the value of adjuvant therapy after curative resection in melanoma of bad risk histology. A breast cancer group and a large bowel group including surgeons, radiotherapists and the Chemotherapy Unit have also been organized to develop adjuvant chemotherapy in solid tumors. In addition, to chemotherapy, immunotherapy in various malignant diseases will be evaluated (A.M.L., melanomas, breast cancers).